1. Field of the Invention
The present invention relates to a horse training cart or sulky, and specifically to an adjustable hydraulic brake system for such a cart.
2. Prior Art
In training a horse for sulky racing it is sometimes desirable to have the horse pull a heavier load than a sulky. Weighted sledges have been used, but adjusting the drag of a moving sledge is difficult, and due to their dissimilar designs sledges are an awkward substitute for racing sulkies. Another prior art technique, taught by U.S. Pat. No. 2,892,514, provides a friction brake for sulky wheels. The prior art brake system applies a constant drag which can be changed only by stopping the sulky, disassembling the brake, and substituting different brake springs. There is a step difference between the braking force applied by different springs; continuous adjustment to degrees of braking between the spring sizes is not available. The brakes wear out and must be periodically replaced. There is, therefore, a need for a trotter exercise cart brake system which can be adjusted over a continuous range, while moving, which will not require brake shoe replacement, and which is otherwise operationally similar to a racing sulky.